Technological advances in IC materials and design have produced generations of ICs where each generation has smaller and more complex circuits than previous generations. Functional density (i.e., the number of interconnected devices per chip area) has generally increased while geometry size (i.e., the smallest component (or line) that can be created using a fabrication process) has decreased. This scaling down process provides benefits by increasing production efficiency and lowering associated costs.
Such scaling down has also increased the complexity of processing and manufacturing ICs and, for these advances to continue to be realized, further advances in IC processing and manufacturing are also needed. For example, three-dimensional transistors such as a Fin Field-Effect Transistors (FinFETs) have been introduced to replace planar transistors. Although existing FinFET devices and methods of fabricating FinFET devices have been generally adequate for their intended purposes, they have not been entirely satisfactory in all respects. Improvements in this area are desired.